Hey. I have owned a 170-500 lens, 150-500 lens and i must say that the 150-500 lens is by far a better lens. Make no mistake the 170-500 is a nice lens but you need to know what you doing, making sure your shutter speed is high etc... The 150-500 has OS so its a bit easier... How ever i sold the 150-500 and bough myself a 400 f5.6 L lens from canon and wow what a lens. Its light, fast, and IQ is awesome. I see a guy on ODP is selling one for R9.5k which is not a bad price at all for the lens.

Yes the 400 does not have that reach of the sigma of 500 but if you get a good photo then you can always crop, problem solved.

There is not much price difference between the two (150-500 sigma, and 400 f5.6) second hand that is. so my thoughts would rather get the 400L you wont be sorry!

Many pro. photographers that take BIF either have or started out with this lens.

I have no intention to knock Sigma, Tokina, or any other brand but in my experience, the facts are as follows:

My frst two lenses from 1996 were Tokina 28-70 and Sigma 70-300;Purchased a 100-500 manual focus Vivitar lens (what did I know about photography??);Forth lens in 1998 was the Sigma 170-500 (to replace the manual Vivitar);all lenses for Nikon mount for use on N50 Film camera

While the pic's were OK, few were great. Second Hand body (F100) added to collection, which came with a 24-120 Nikon lens and the improvements were startling (which I put down to the improvement in the new body).

Moved to a D70 digital body (6.1mp) and the 18-70 kit lens and retained all the other lenses. Backwards move for me as the D70, while an iconic camera, could not match the F100 film camera in any respect (shooting Velvia slide and ASA 100/200/400 film, depending). Thought I had a dud D70, sent in for calibration, returned with no difference in quality. Finally put the output down to my personal photographic skills (or rather lack thereof) and not the equipment.

Purchased a Nikon 50mm f1.4 and got stunnning results with all my (both digital and film) bodies and put that down to the fact that it was an f1.4, high quality Nikon lens. However, this did not point out to me that the other lenses I had were of lower quality, but rather that they were just slower lenses.

Earlier this year, I finally took the plunge and upgraded my body to the new D7000, when the whole federal reserve bank dropped (ie. Not just the penny ). The cause of all of my poor quality pictures had been the lower quality lenses all along. The D7000 is just so damn good that all the flaws in all my old equipment bubbled to the surface and became exposed once and for all.

So again I took the plunge and replaced my (trusty?) 70-300 Sigma, now 15 years old, with the new 70-300 Nikon VR lens and again, the improvement was dramatic and immediate. Cropped pictures with the new Nikon glass are superior to the uncropped pictures taken with the Sigma 170-500.

Equipment-wise, I have what I need. Sure, there may be lots that I want, but I have learned the hard way, to save for what I want rather than compromise on quality and rush into buying an interim product and then having to forego on possible quality of the output. Personally, given my history, I can do without....

(PS.. I still question what I know about photography) (PPS.. My D70 is now taking the picture quality it was originally designed to do from the start....IT'S ALL ABOUT THE GLASS)

"Take nothing but memories, leave nothing but footprints"

Photographs help to crystallize memories, but cannot be seen to be a replacement of them!

H.E. It seems you are like me . I take pics because it gives me pleasure , not because I want to enter photographic competitions with it . I see something in the distance , and even with bino's I cannot have a really good look at it ,so I take a pic to have another look at it later . I have a sigma 70 - 300 , but sometimes just do not get the reach , so I bought the 50 - 500 sigma . Yeah , you can crop and sharpen and enhance pics , and change the colour settings and RAW , and composition , using photoshop or whatever . Good grief , you can do about anything with modern-day digital technique , but hey man , I am not that fanatical about it . I just enjoy it

Tread softly , and let your departure not be spoiled by the damage of your arrival

Speaking of competitions and Sigma lenses; don't be dismayed, I have had a few pics in the Getaway magazine published before, won one competition and got an entry published in the Captured Experiences book - all with photos taken by my "lesser" Sigma...

Now I am no expert on these matters, and enter the fray with some fear and trepedation. I own a 170-500 Sigma, and I am happy with it, despite it being slow. But then again, for photography, especially in KNP, unless you are wanting to take competition winning photos, it does a pretty good job for the price if you merely want the pleasure of photogrphy and retain some memories. It can even do spme pretty good BIF shots if you are patient enough. If budget is a consideration, consider a Sigma 70-300 Macro lens (which I also have) and add a x2 converter- very acceptable alternative to a 500mm lens. These are going for about R17-1900 and you can get a good x2 converter for a bit more. In addition you will also have a acceptable macro lens thrown in.

Switchback wrote:Correct on your first statement, the 150 - 500mm is also a newer lens than the one they call the "bigma", the 50 - 500mm lens.

Only true if you are referring to the original 50-500 (Bigma) without optical stabilization. The current 50-500 OS model is the latest of Sigmas 500mm zooms. It is however, also substantially more expensive than the 150-500.

Switchback wrote:Obviously the big selling point of the bigma is its range, but that is also it's downfal...

Conventional wisdom does say that the extreme range of the Bigma (10 x zoom) should result in a reduction in quality. Interestingly enough the majority of comparative reviews report the IQ of the 50-500 to be slightly better than the 150-500. This is true of both the original and current models. That said if I had the choice between the 50-500 without OS and the 150-500 I would probably go for the 150-500 due to the OS advantage.